1. Field of the Invention
The present invention relates to an improved method of manufacturing a thin film transistor panel.
2. Description of Related Art
In order to reduce the size of semiconductor devices, something which is becoming increasingly important in the semiconductor industry, signal lines within these devices are being formed within multi-layers. The insulating layers of the conventional semiconductor devices are generally formed of material having low permittivity in order to minimize any interference of signals transmitted via the signal lines. Also, the signal lines formed in different layers are electrically connected to each other via contact holes.
Flat panel display devices, such as liquid crystal display (LCD) devices and organic light emitting display (OLED) devices, adopt the semiconductor devices and structures of organic insulating layers to control pixels. In particular, in order to increase their aperture ratio, the display devices employ pixel electrodes formed to overlap the signal lines. Also, in order to decrease their parasitic capacitance, the display devices employ an insulating layer between the pixel electrode and the signal line, which is made of organic material having the low permittivity.
Generic organic layers having photosensitivity (also referred to as photosensitive organic layers) are used and formed into desired shapes through exposing and developing processes without using a separate etching process. When photosensitive organic layers are patterned, their required thickness is about 4.6-4.7 μm or more in consideration of a decrease in the thickness during, or as a result of, patterning of other layers. The amount of light required for patterning the photosensitive organic layers is about 3-4 times greater than that required for patterning generic photosensitive layers, thereby increasing the exposing time. In considering the time required for implementing a photolithography process, the total combined processing time is substantial, which may result in diminished productivity. In addition, the amount of organic material consumed increases, as well as the amount of clean up time due to, e.g., removing the deposits of organic material on the etching devices, which in turn, may cause the costs of production to increase.
What is needed, therefore, is a more efficient way to manufacture thin film transistor panels.